LISA and speedFeb 12th, 2008 | By Ian Poulton | Category: Personal Columns
The CSE in General Science didn’t provide much help last night. The lecturer was a brilliant experimental physicist from Glasgow, and never having done physics, let alone know exactly what an experimental physicist was, (did it mean that you could shift gravity around a bit to do tests or see what happened if you shifted the Earth by a few degrees?), I was at a loss.
The only reassurance was that the lecture theatre was named after the brilliant Austrian physicist, Erwin Schroedinger, who won the Nobel prize for physics in 1933. Schroedinger was in Dublin from 1940 until 1955, before returning to his native Vienna, but when he died he chose to be buried in the tiny Tyrolean village of Alpbach.
Standing at his grave in Alpbach churchyard last month, I thought he was a man who had chosen his spot well, completely unaware that he had been in Dublin before me. If nothing else, I had in common with Schroedinger a liking for the same places.
The lecture was on LISA, not a young lady, but Laser Interferometer Space Antenna, a multi-billion project to launch three spacecraft that will form a triangle with sides of 5 million kilometres with laser beams between the craft; the intention being to measure waves of gravity coming from events in space and even pick up echoes of the beginning of the universe.
Rooted in Einstein’s thought, Gravitational Wave astronomy is intended to provide insights into how the universe came to be. Matters that might be of interest to theologians, (if they ever detached themselves from church things).
Questions afterwards were even more complex than the lecture itself. One person challenged the idea that gravity waves could travel at or near the speed of light, quoting someone’s work in proof of this. I pondered this afterwards. If light is faster than gravity: at the beginning of the universe, what prevented all the light escaping before the gravity could keep it in check?
Doesn’t Einstein say that gravity causes even light to bend back to its source? How does it trap light if its waves are so much slower?
If it were not for the fact that I would probably look a complete fool, and would not have the right words to ask the question, I would write and ask.